1. Field of the Invention
The present invention relates to optical character recognition which converts character images in image data to character code data.
2. Description of Prior Art
In character recognition by using an optical character recognition apparatus, characters in a text image in a document are recognized. As to a document including text image and the other image, it is known to further recognize the layout of the document and to arrange data of the other image at relevant positions in the layout as bit map image data. The layout, the character code data and the bit map image data are outputted as one file.
However, when a document has characters on a background image, after converting the character image data to character code data, it is difficult to synthesize the recognized characters (character images based on the character code data) with the original image data. This is due to difference in the font and the positions of the characters in the original image data with the counterparts based on the conversion data.
In prior art character recognition, it is known, for example, as shown in FIG. 1, to convert the character image data in a document while not to output the background image. It is also known, as shown in FIG. 2, to superpose the character code data obtained by the conversion on the image data of the document and to output the superposed image. However, in the former, the background image is not reproduced, and the information is lost partly. In the latter, the output image of the character code data is liable to be shifted from that of the character image data, or the output image becomes obscure.